Bottlehead Forum

Bottlehead Kits => BeePre => Topic started by: johnsonad on March 28, 2013, 05:15:37 PM

Title: My take on the BeePre
Post by: johnsonad on March 28, 2013, 05:15:37 PM
My BeePre is finished and playing as I type this post :)

For those who haven't started it or are considering this build, the Bottlehead team have hit a home run!  It's a pretty easy build thanks to the best manual I've ever seen and Bottlehead's best to date.  I took my time over a couple of weeks and enjoyed every bit of it.  Like others have posted, I printed the manual and checked off each step while making notes on the sides of the manual.

Here are the details of the build.  The top plate and bell housings were powder coated in black wrinkle to give it that 30's radio look. I  used satin model paint to blacken out the RCA jacks, transformer screws and BeeQuiet top plate.  The flat topped black screws were from another project.  A sharpie was used to to blacken the edges of the 9 pin socket.  The knobs are vintage 30's pieces thanks to my HAM buddies.  Once I find a third mushroom style I'll replace that arrow head on the selector switch.

I attempted a vintage look with the base but it didn't turn out as well as I would have liked.  This was my first attempt at staining and the alder doesn't soak it up like a soft wood.  It was finished with tung oil and has a beautiful look in the light.  A buddy is building me a base in black walnut.  I'll post some picks once finished.

As for the working components I made the following parts swaps and adjustments.
1. Two sets of RCA outputs, no balanced output
2. Mills 8 Ohm resistors
3. Nichicon KA series 10,000uF electrolytic
4. Neotech OCCC solid 20g wire through 98% of the signal path and the BeeQuiet
5. Audio Cap 10uF output caps
6. Elma selector switch

Yes all this was done without listening to it in the standard configuration but, a couple of these mods would have been a PITA to try and retro fit. 

A few notes on the build. The signal wires were wrapped in aluminum foil, then with a drain wire and lastly with the Tech Flex.

If you plan on using oversized caps and the BeeQuiet, I would recommend installing the BeeQuiet first.  The Audio Caps are significantly larger then the stock caps and didn't get close to the base plate in my build.  To secure them, I used a two hole grounding washer over a nylon washer and screwed in to the top of the C4S board.  Magnet wire was then wrapped around the cap and secured to the two holes in the grounding washer.  It's not elegant but works well and keeps the caps off the BeeQuiet resistors.  You will need to bend a few of them upright to shoehorn the caps in. 

I'm no photographer and it looks much better in person but here is an attempt.  I'll comment on sound in another post :)
Title: Re: My take on the BeePre
Post by: johnsonad on March 28, 2013, 05:17:41 PM
A couple of pics of the working end.  The second is what I used to tie to cap down.
Title: Re: My take on the BeePre
Post by: earwaxxer on March 28, 2013, 06:22:40 PM
cant wait for the listening impressions!  :)
Title: Re: My take on the BeePre
Post by: BNAL on March 29, 2013, 05:12:37 AM
Aaron,

The BeePre looks great.
Title: Re: My take on the BeePre
Post by: HF9 on March 29, 2013, 06:07:52 AM
Great work, inside and out!
Title: Re: My take on the BeePre
Post by: KevO on March 29, 2013, 08:33:34 AM
Aaron,

That is a real beauty!

The red wiring on the black underside is terrific.

Great workmanship.

How is it sounding?

Kevin
Title: Re: My take on the BeePre
Post by: johnsonad on March 31, 2013, 06:38:20 AM
Time for some initial listening impressions.  First off, I had an intersting start but after a phone call to Dan everything was sorted out.  System synergy is different for everyone and I ran into the perfect storm of 100dB sensitive speakers and a very high gain SS power amp (old Quad 303 at the moment) with the BeePre.  My system needed a Lpad in front of the power amp to lower the gain.

I've only got around 30 hours on the BeePre but from the beginning it sounded great and continues to improve.  It must be the DHT magic as I find myself mesmerized by the sound coming from my speakers.  The best way I can put it is that the BeePre has added a sense of realism and greater emotion to my listening experience.  It images very well, has wonderful tone and a blackness between notes that I appreciate. 

I'll post more as it continues to break in :)
Title: Re: My take on the BeePre
Post by: earwaxxer on March 31, 2013, 07:49:51 AM
sounds like a great start! - looking forward to some comparisons!
Title: Re: My take on the BeePre
Post by: Paul Birkeland on March 31, 2013, 02:23:37 PM
An amp that makes 45 Watts into 8 Ohms from 0.5V (your Quad 303) has just under 32dB of voltage gain.

The Seduction phono preamp, by comparison, had 40dB of gain.

This isn't normally the end of the world, but 100dB speakers will perform really well with a lower gain amp (12-18dB).

The L-pad is an outstanding solution, I have found that every vintage design that I have owned or built has needed a ton of padding at the input, usually at least 6 dB, normally closer to 15.

(But of course we are always here to help with these things)
Title: Re: My take on the BeePre
Post by: johnsonad on March 31, 2013, 02:40:42 PM
And you all saved the day! This old 303 has an amazing tone for a SS amp and is hard to part with. I've got a few other amps around but I keep coming back to this Quad. Thank you all for making it usable in the current system :)

The BeePre continues to impress! It's new and I hate to comment to much on new parts of the system until I've grown accustomed to them but it really is an amazing preamp :)
Title: Re: My take on the BeePre
Post by: xcortes on March 31, 2013, 03:10:19 PM
I should try one of those Quad amps one day with the Quads. Have you hear that combo?
Title: Re: My take on the BeePre
Post by: johnsonad on March 31, 2013, 03:19:17 PM
Nope as the builder is still broke and owes me $4500 two years later.  I've got a second one sitting around awaiting a Net Audio rebuild. Let me know if you're interested :)
Title: Re: My take on the BeePre
Post by: mp9 on April 02, 2013, 11:43:23 AM
I'm assuming the Neotech wire johnsonad used is of higher quality then the supplied 24AWG Cat 5, and he could've stuck with a 24AWG gauge (Neotech or other), wire, is there a appreciable reason for going to a 20AWG hook up wire?
Title: Re: My take on the BeePre
Post by: Doc B. on April 02, 2013, 11:54:11 AM
This is a new kit. We built it the way it is shown in the manual. We don't have any experience with the way other people are modifying the kit as they build it, and thus we aren't yet qualified to comment on whether the changes are better, worse or indifferent. My suggestion is to build it stock. You can mod it later and that way actually have a point of reference for comparisons.
Title: Re: My take on the BeePre
Post by: johnsonad on April 02, 2013, 12:26:44 PM
I'm assuming the Neotech wire johnsonad used is of higher quality then the supplied 24AWG Cat 5, and he could've stuck with a 24AWG gauge (Neotech or other), wire, is there a appreciable reason for going to a 20AWG hook up wire?

20g is as small as I've been able to get it with Teflon coating and I happened to have 50' or so of it sitting in a drawer. It was a pain to work with but not horrible.

I was too lazy to build it twice and instead used some parts and wire I've had good experiences with in the past.  I doubt there will be much sonic difference and the only way to trial it would be to A/B it against another BeePre.
Title: Re: My take on the BeePre
Post by: mp9 on April 03, 2013, 02:28:07 PM
I'm assuming the Neotech wire johnsonad used is of higher quality then the supplied 24AWG Cat 5, and he could've stuck with a 24AWG gauge (Neotech or other), wire, is there a appreciable reason for going to a 20AWG hook up wire?

20g is as small as I've been able to get it with Teflon coating and I happened to have 50' or so of it sitting in a drawer. It was a pain to work with but not horrible.

I was too lazy to build it twice and instead used some parts and wire I've had good experiences with in the past.  I doubt there will be much sonic difference and the only way to trial it would be to A/B it against another BeePre.
I'm looking into possible upgrades that i'd rather not have to do twice, trying to decide if some of my ideas are worth the money or if it's better spent elsewhere on the project.

I came across Neotech 24awg Silver/teflon wire for $2.95/foot (big diff from $9.45/foot @ partsconnex), and am trying to decide first if it's the real deal and secondly, if its worth doing. About how many feet of the 20awg did you use?

Also been considering teflon tube sockets, again i don't know the advantages over the kits stock ceramic tube sockets.

I'm going to stick with the two supplied 10uf caps for the build as they won't be too complicated to swap out latter if i read of good benefits  of such.

Also and strictly for cosmetics, been wondering about having the top plate and transformer bell ends chrome, nickel or copper plated, of course i may get sticker shock with that one, lol.
Title: Re: My take on the BeePre
Post by: johnsonad on April 03, 2013, 02:37:22 PM
The price for the Neotech seems way off. If it isn't a reputable seller you may want to think twice on that.

The tube sockets supplied are great and I can't think of a reason to swap them. Besides a lot is attached to those sockets and an alternative may not work well with the design.  I've never understood fancy tube sockets, they need to fit the design and hold strong tension on the tube pins.

Plating is expensive. If you get a good price, let us know where.

I used roughly 17 feet of wire give or take a foot or two.
Title: Re: My take on the BeePre
Post by: Paul Birkeland on April 03, 2013, 05:31:42 PM
I find the Teflon 4 pin sockets to be pretty tough to work with.  If you're going to use them, you have to plan to be able to get your pliers around them once in a while to tighten them up.  This works poorly with the BeePre though.

There's a gold plated version of the stock socket on PCX if you want to add a little bling and know that you wont' introduce unpredictable consequences...
Title: Re: My take on the BeePre
Post by: mp9 on April 03, 2013, 06:00:13 PM
- thanks C.B., i'll definitely skip that idea.

- johnsonad, so far i've found the neotech 24awg silver at Take Five Audio for ~ $7.50/foot http://www.takefiveaudio.com/mall/shopexd.asp?id=845 a little closer but still far from the Ebay sellers $2.95/foot http://www.ebay.com/itm/370719150903?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

Hard to imagine the guy not selling out of his stock at that $$ if it is what he says it is? The guy claims to be selling his old stock. Btw, have you seen the Audio Note factory tour video, my guess, Peter Q would've bought up the entire spool had he not cornered the market years ago - (for your entertainment),  http://www.avshowrooms.com/Audio_Note_Co.html

Anyway the guy has good feedback, customers seem satisfied with their purchases of the silver neotech wire, idk, maybe it takes a metallurgist to discern the difference??

Nothing specific on Audio asylum's Shady Lane forum, unless it's this guy at it again - http://db.audioasylum.com/mhtml/m.html?forum=shady&n=4847&highlight=neotech&r=&search_url=%2Fcgi%2Fsearch.mpl%3Fforum%3Dshady%26searchtext%3Dneotech%2B
Title: Re: My take on the BeePre
Post by: earwaxxer on April 03, 2013, 06:20:23 PM
I have used this site for my wire - great service no complaints.
http://www.homegrownaudio.com/solid-core-silver-wire/
Title: Re: My take on the BeePre
Post by: corndog71 on April 03, 2013, 06:27:48 PM
I have used this site for my wire - great service no complaints.
http://www.homegrownaudio.com/solid-core-silver-wire/

Seconded!  I've been a fan for years.  Easy to bend and strip and sounds great.  Their copper wire is no slouch either.
Title: Re: My take on the BeePre
Post by: johnsonad on April 03, 2013, 06:31:20 PM
Is your heart set on silver?  Do you run all silver through your system already?  I've always considered wire as a method of tone control in some respect and could never justify or afford an all silver system.  CAT 5 is suprisingly good cable.  At least one member here used it for his interconnects and I dream of owning a system as nice as his someday.
Title: Re: My take on the BeePre
Post by: mp9 on April 03, 2013, 07:58:49 PM
- well not exactly. My amp is wired with silver but lacks silver opt's etc. I've yet to play around with silver for the wide band driver cabling, my current drivers i most interested in voice coils are not silver although i have others that are.

I don't think Cat 5 is bad either. Been using both half of a Cat 5 plenum wire per - & +, as well as a single strand per of Cat 5 plenum wire for the speaker cables more then the Kimber 8tc i have. Only thats easy to change, doubt i'd ever bother rewiring the bee if i didn't have to for other reasons.
Title: Re: My take on the BeePre
Post by: johnsonad on April 04, 2013, 08:06:04 AM
I feel ya and that's why I wired it once with the Neotech. 40 plus solder points is enough the first time around ;)
Title: Re: My take on the BeePre
Post by: tsingle999 on April 04, 2013, 08:23:53 AM
In my limited experience i have always preferred the sound of copper over silver. Copper seems to help the low end and silver the high end from the experiments i've tried.
Title: Re: My take on the BeePre
Post by: johnsonad on June 30, 2013, 10:26:27 AM
After capacitor experiments in my S.E.X. amp and a thread stating I could use a lower valued output cap, today I replaced the 10uF Audiocaps with a pair of 5 uF Auicaps I had sitting around. These will need break in but from the beginning there seems to be more top end and air than before.  I'm gojng to run them in 100 hours and report back. My hope is that they will allow me to get the EML's back in and even out what was missing before.
Title: Re: My take on the BeePre
Post by: johnsonad on July 27, 2013, 01:47:13 PM
Time for some updates on the BeePre project.  I've been having fun with tubes and output capacitors.  The tubes I'll rank based on personal and system preference which coincides with a buddy who did the listening tests with me over the course of a months worth of Saturdays. 

1. EML 300B
2. EH 300B Gold Grid
3. Russian 6C4C
4. Sovetek 6B4G
5. TJ 300B mesh plates

There is just something special about these EML's.  Both Mike and I felt mesmerized every time we put them back in the system.  They are the tube for me (so far!).  Maybe I'll try the EML 300B mesh plate once PJ figures out the filament supply for 1.5 amps. Now getting them to the correct filament voltage took significant trial and error.  With the Parts Connexion sale and a few more Mills values I finally got them within less than 1%.  For my BeePre this took a 27 Ohm (4.97v) and a 33 Ohm (4.99v) resistor.  These tubes took a good 100 hours to sound nice so if you have a pair sitting around or are thinking of taking the plunge, let them burn in!

Cap rolling can have a significant effect also.  So far in full values I've tried the Audiocap 10uF and some Russian PIO's 12uF.  I've bypassed them with ClarityCap 1uF, Russian FT-1 0.01uF, Russian FT-2 0.1uF and Russian SSG-3 0.1uF caps.  I also briefly tried a pair of Auricap 5uF which didn't work out that well into a 10k Ohm load impedance.  Today I put in a pair of Jupiter 10uF caps which still need to break in.  I've found the Audiocaps to be rolled off but to do well with voices and the lower mid range.  There is just something not quite right about them.  Byassing did change the sound but not enough to give a complete package.  Don't get me wrong, I like the sound of the Audiocaps and they have spent longer in the BeePre than any other cap so far.  The PIO's were in for a week.  I bypassed them with all of the Russian teflons and the silver mica caps.  They sounded better on their own and quite good.  They would have stayed longer if the Jupiter's didn't arrive.  Maybe not the end all be all in detail or dynamics but very nice over all and more correct than the Audiocaps.  The Jupiter's have a couple of hours on them so far but I can tell already they are going to be special.  They took a little work to fit and to isolate them from the heat sinks but so far so good.   FYI, I emailed Jupiter about the flat stack HT caps and they are conservatively rated at 70 C, 158 F.   

I continue to be ever impressed by the BeePre. This the best preamp I've owned to date. More to follow :)
Title: Re: My take on the BeePre
Post by: earwaxxer on July 27, 2013, 02:42:50 PM
Nice review Aaron! - Thank you! Keep in comin!
Title: Re: My take on the BeePre
Post by: johnsonad on July 27, 2013, 03:43:50 PM
Thanks Eric!

Another topic to add and that's microphonics. In my experice so far I've found the best sound is achieved by the lowest microphonic tube. So far the best I've experienced is the 6c4c. I can bang hard on the deck plate with very little resonance or ringing to the speakers (lead weights only). Second are the EML's. The lead rings, Herbies dampeners and sorbathane footers all help to some degree. I've got some Tenderfeet and other rings on order to see if they help anymore then what I already have. This design is so sensitive that to my ears, the more you can lessen the ring, the better the overall sound. If you look at my ranking, I put the EH above the 6c4c and that's so far due to the lack of break in of the tubes. The EH's have a horrible ring but somehow they still sound great. More to follow as the 6c4c's break in along with the Jupiter's.
Title: Re: My take on the BeePre
Post by: Paul Joppa on July 27, 2013, 06:04:20 PM
Yeah, the importance of microphonics is a really curious issue. We sidelined the Quickie for years because of them, based on just a few minutes listening. But once we did more listening and actually put it out there everyone (us included) started to hear it's virtues as well. BeePre was the other way around; we all agreed it had the magic in spite of its microphonics.

Are microphonics, like ultra-low measured distortion, another false god of our idolatry?  :^)
Title: Re: My take on the BeePre
Post by: johnsonad on July 27, 2013, 06:19:27 PM
  I'm not sure at this point Paul.  I will say that when microphonics are low, I hear more of and deeper into the music. Remember that when I first fired up my BeePre I could talk a foot away from the tubes and it would ring through the speakers.

It wasn't a  turn key perfect design for my system (too much gain) but man can it sound good If you are willing to do a little trial and error. I still feel this is a home run for the Bottlehead team. My system wows all that have heard it and I only nit pick because I'm in front of it everyday.
Title: Re: My take on the BeePre
Post by: Chris on July 28, 2013, 06:30:19 AM
Beautiful Bee pre.. is that a beautiful piece of koa I see?...
Title: Re: My take on the BeePre
Post by: johnsonad on July 28, 2013, 06:32:35 AM
No, very figured black walnut with a tung oil hand rubbed finished. It looks much better in person.
Title: Re: My take on the BeePre
Post by: Chris on July 28, 2013, 07:28:36 AM
Wow, I have worked with Koa before (can be a very beautiful wood), and this looks quite alot like it... Nice piece...
Title: Re: My take on the BeePre
Post by: johnsonad on July 28, 2013, 08:06:30 AM
Thanks Chris but praise goes to my carpenter. All hand cut dove tail joints and each side has a different personality. I'm going to try and get him to build similar bases for all of my BH kits.
Title: Re: My take on the BeePre
Post by: johnsonad on July 28, 2013, 08:32:12 AM
This morning I got around to measuring top plate temperature differences with tubes. I used my trusty kitchen thermometer and rested it on the chassis plate front to back near the right tube. With the 6c4c which draws 1 amp the plate stays at 110 F. With the EML 300B which supposedly draw 1.3 amps, it raises to 118 F. The house temp is set at 73 F. 
Title: Re: My take on the BeePre
Post by: johnsonad on July 28, 2013, 09:57:41 AM
I'm trying to listen through this cap break in and I'm using a full Wagner Ring cycle (Solti, VPO) to do it. I can't explain it but cap break in is real. In the BeePre, the tube/cap combo is highly adjustable. So far so good on the Jupiter's.
Title: Re: My take on the BeePre
Post by: HF9 on July 31, 2013, 11:25:00 AM
I'd love to see a photo of the amp with the Jupiters inside. They are relatively large, how did you rig them up?
Title: Re: My take on the BeePre
Post by: johnsonad on July 31, 2013, 12:36:22 PM
I can do that.

Today I listened to the Jupiter's at the 100 hour mark and feel that they have a while to go still. I'm going to pull them out and put them in the burn in rig for a few weeks tomorrow.  I contacted Chris at Jupiter and he said they can take a while in low output usage such as in the BeePre.

For the Jupiter's I had to add about 3 inches of wire to get them to reach. Then I put spacer insulators against the cap and let them gravity hang against the heat sinks. It worked better than expected and they stay just warm  to the touch when you reach underneath the amp.

I also received some Herbie's Tender Feet (tall, soft) today and put them to use. I didn't notice any sound difference but they sure look better and raise the BeePre enough to drop the top plate measured temp by one degree.
Title: Re: My take on the BeePre
Post by: johnsonad on August 03, 2013, 05:07:00 AM
While the Jupiter's are burning in, I put back in a pair of caps that caught my attention but were not given a fair chance do to the arrive of the Jupiter's.  They are a Russian KBG MN PIO caps.  To get the 10uF or greater value with the caps I had on hand I had to parallel a couple of 6uF.  These had been previously burned in and sounded great from the beginning.  Really, these sound great and seem to be the sound I was looking for in combination with the EML 300B's.  I'm a little afraid that when the Jupiter's are ready, I'm not going to like them as much as these Ruskies. 

Sound changes which are system and user preference based are hard for me to describe.  The KBG's have great attack and decay of notes, sounds are presented in a nice dark background, there is plenty of ambient room info (though not as much as others I've tried).  My favorite part is the tone.  Music is a little rounder or more whole, almost palpable.  Piano notes decay and you feel them linger.  Female voices are inviting.  Basically I feel more emotionally involved when using this combo of KBG's and EML tubes. 

I held off posting on these until I secured a pair of 10uF caps and a few just popped up on the ePay (no association of course).  They are cheap and worth giving a try but I'll warn you ahead of time, they don't fit.  I have them on foot long leads sitting to the sides of the preamp. 

Second, an update on tubes.  The EML's are the sound for me. I'm keeping a pair of 6C4C as they will work with the modified current settings needed for the EML's and offer a slightly brighter sound for those times I need reminding how good the EML's are (to my ears). 

Lastly, once I'm finished goofing around with capacitors, I'm considering the choke mod that Xavier did and listen for any change for the better.
Title: Re: My take on the BeePre
Post by: earwaxxer on August 03, 2013, 07:53:01 AM
Thanks for the in depth reporting Aaron!
Title: Re: My take on the BeePre
Post by: HF9 on August 03, 2013, 05:26:28 PM
Very interesting impressions Aaron. The Russian caps always prove to be great values. I did note that the KBGs are offered in 10uf 200V versions. They're rather large at 65mm x 35 mm x 108 mm, but maybe some creative mounting might work. One thing I noticed was the +/- 10% tolerance, so you might want to get four and hope that two are close enough to be a good match. Please let us know your findings when the Jupiters are burnt in.
Title: Re: My take on the BeePre
Post by: johnsonad on August 04, 2013, 07:36:28 AM
Matching capacitors will make zero audible difference in this application. From my experience with these caps, they are close enough, especially the 10% versions.

Capacitor matching is important in crossovers and in the RIAA of a phono stage where they set the curve.
Title: Re: My take on the BeePre
Post by: HF9 on August 04, 2013, 06:02:01 PM
Gotcha, I always like to match caps and resistors on each channel, probably just a CDO thing.

CDO is kinda like OCD, but in alphabetical order, the way it should be ;)
Title: Re: My take on the BeePre
Post by: johnsonad on August 11, 2013, 05:38:17 AM
A small update. I'm really enjoying the pairing if the BeePre and S.E.X. amp so far but with this large change I've got to re-learn the sound if the system before tweaking any more. I've found one area to revisit and that's the noise transmission through the BeePre.

With the Quad amp I had it to an extremely low level due to compensating for the extreme gain of the Quad. The SEX does not have this gain and I'm now hearing more of the ring through the BeePre tubes. So far I have Herbies rings on both the EL84's and 300B's, lead rings on the 300B's and Herbies Tenderfeet under the chassis. The BeePre is 6 feet away from the left speaker against a wall.  Not ideal but it's the best I can do with this room at the moment. If I sit next to the speaker with my ear near the large driver and talk in the direction of the BeePre I can hear it ring through the speaker at a low level. It seems to only excite the tubes in a certain frequency range, around a males voice level and a little lower.

The vibration is both air and chassis born and efforts are focused on these two areas. For the airborne vibration I'm going to place some dense rock wool between the preamp and the direction of the speaker.  For the chassis born vibration I'm going to try the same approach that worked well with my Altec horns and place Dynamat Xtreme on the underside of the base plate. My decibel weighted multimeter is in for service but once it returns I should be able to give some hard numbers to these efforts.

One last thing, the SEX amp has no business sounding this good!
Title: Re: My take on the BeePre
Post by: johnsonad on August 11, 2013, 09:30:46 AM
The airborne isolation with rock wool failed. It could be that my voice is enough to cause resonance through my cheap home made rack and cause some vibration. Who knows but it's low enough I can live with it and I don't hear anything outwardly different when listening to music which is all that really matters.

I'm having a very hard pulling myself away from the BeePre/SEX combo. Thankfully it's Sunday!
Title: Re: My take on the BeePre
Post by: Paul Birkeland on August 11, 2013, 11:05:40 AM
It might help to add some weight to the rack.
Title: Re: My take on the BeePre
Post by: johnsonad on August 11, 2013, 12:18:16 PM
The top shelf has 150 lbs worth of TT and R2R machines. The second rack is the preamp level. I'll give the extra weight a try.
Title: Re: My take on the BeePre
Post by: earwaxxer on August 11, 2013, 12:47:14 PM
One thing I like about living here in AZ. No basement. Concrete tension slab floors. Put it all on the floor and your set....
Title: Re: My take on the BeePre
Post by: corndog71 on August 11, 2013, 02:38:27 PM
One thing I like about living here in AZ. No basement. Concrete tension slab floors. Put it all on the floor and your set....

I don't know, Eric.  That could lead to a "hard" sound. :P
Title: Re: My take on the BeePre
Post by: earwaxxer on August 11, 2013, 02:46:56 PM
No Rob... Tight and in "control". Thats the way we like it here in AZ!
Title: Re: My take on the BeePre
Post by: johnsonad on August 11, 2013, 02:55:27 PM
If I had the room And no wife I would happily put all of the components in the floor ;)
Title: Re: My take on the BeePre
Post by: earwaxxer on August 11, 2013, 03:01:13 PM
Aaron, I have a wife. Its just a matter of "training". You put it all in front of the TV, on the floor. They get used to it...
Title: Re: My take on the BeePre
Post by: earwaxxer on August 11, 2013, 03:06:02 PM
All right, in the interest of honesty and self disclosure, I do have some stuff "hidden" behind the TV in the entertainment system build. But, still, how much shit do you have to display at one time? Put your best stuff out there. The rest goes in the closet. The beauty of that is that she forgets about how much crap you have when you want a new piece! See! Smart haaa?
Title: Re: My take on the BeePre
Post by: johnsonad on August 11, 2013, 03:34:09 PM
You may have something there Eric. Looking at my rig I can probably work a good percentage of gear on the floor. I may try this in the future!
Title: Re: My take on the BeePre
Post by: Chris on August 11, 2013, 03:37:09 PM
Until she enters the closet reaching for the christmas decorations and has an old Vector Research receiver fall on her head...I can hear it now..OW!wwwwWWWWAAAAAAXXXXXXXEEEERRRRR!!! 
Title: Re: My take on the BeePre
Post by: HF9 on August 11, 2013, 07:15:36 PM
So.... I'm super curious, any news with the burnt-in Jupiter caps? :)
Title: Re: My take on the BeePre
Post by: johnsonad on August 12, 2013, 01:23:29 AM
They are sitting and waiting until I have a better feel for the BeePre and SEX Combo
Title: Re: My take on the BeePre
Post by: johnsonad on August 14, 2013, 02:03:35 PM
The Dynamat Extreme came in and I applied it to the inside of the wood base and to the available under spaces of the chassis plate. When changing volume on the Bee Quiet it made a slight difference in the length of the ring decay but nothing to write home about. I notice no difference in the airborne ring so it was quickly removed. In my application, using EML tubes, I want to remove heat as quickly as possible. The Dynamat added a layer or two of insulation and the reduction in ring wasn't enough to justify it. Besides, you don't continually change volume when listening so the reduction was a mute point.

I'm going to try other means of mechanically isolating the BeePre and hopefully reducing that airborne ring effect but it's low on the priority list. It is sounding better than ever and I've got a couple of other plans in shippment that I'll post on once tested.  The Jupiter's will get a second chance in a month or so once I get a good feel for the BeePre/SEX combo.  These two sound amazing with my Altec's so much so that I'm kicking myself in the ass for not trying the SEX amp earlier.
Title: Re: My take on the BeePre
Post by: adamct on August 14, 2013, 02:06:23 PM
Out of curiosity, how did you install the Dynamat such that it was easily removable? I thought that stuff had some sort of strong adhesive backing...
Title: Re: My take on the BeePre
Post by: johnsonad on August 14, 2013, 02:16:21 PM
It does if you let it sit too long.  I removed it after 30 minutes or so. It didn't have enough time to stick well enough to remove paint or wood. 
Title: Re: My take on the BeePre
Post by: adamct on August 14, 2013, 02:20:01 PM
Thanks.
Title: Re: My take on the BeePre
Post by: HF9 on August 15, 2013, 02:00:08 PM
Teflon tube sockets might help. They absorb some degree of vibration more than their ceramic counterparts. The latest Teflon sockets coming out of China don't have those little nuts that get loose over time, which is nice.
Title: Re: My take on the BeePre
Post by: johnsonad on August 15, 2013, 02:43:29 PM
Thanks but no thanks. Teflon is pretty hard and those sockets are not the easiest to work with. If my voice from 6 feet away can cause the heater elements to vibrate, I highly doubt an expensive fancy socket will do anything but look nice. Thank you for the suggestion though.
Title: Re: My take on the BeePre
Post by: Grainger49 on August 15, 2013, 02:46:48 PM
Aaron,

Sounds like you need to use your "inside voice" around the Bee Pree.
Title: Re: My take on the BeePre
Post by: corndog71 on August 15, 2013, 03:04:25 PM
Maybe you need to create a box with a good 6" of foam inside to encapsulate the BeePre.  You could always put in a tiny camera and connect it to your tv so you can still see the BeePre.
Title: Re: My take on the BeePre
Post by: johnsonad on August 15, 2013, 03:19:25 PM
Grainger and Rob, thanks  :o.....  I am very very happy with the BeePre but am always trying new things. This is a small issue when compared to how good it sounds :)
Title: Re: My take on the BeePre
Post by: Doc B. on August 15, 2013, 03:22:35 PM
The ultimate solution is to put the electronics in a different room than the speakers. Fixes resonance issues and heat buildup in the listening area. Of course almost no one has the space to do this.
Title: Re: My take on the BeePre
Post by: Paul Birkeland on August 15, 2013, 04:45:28 PM
Thanks but no thanks. Teflon is pretty hard and those sockets are not the easiest to work with. If my voice from 6 feet away can cause the heater elements to vibrate, I highly doubt an expensive fancy socket will do anything but look nice. Thank you for the suggestion though.

Is this with both the EML's and the EH's?
Title: Re: My take on the BeePre
Post by: KevO on August 17, 2013, 07:58:48 PM
The Electro's are microphonic in my BeePre when I am withing 3 feet and speaking loudly. The Vikem rings help.

The Sophia carbon plate tubes are almost as microphonic as the Electro Harmonix.

My Beepre has teflon sockets. Teflon has some internal damping properties,, but it is still pretty hard. Not cost effective IMHO.

I was thinking about glass cylinders to surround the tubes. Some small rubber feet to raise it a 1/4 inch off the chassis. Chimney effect should keep things cool.

I'll see if I can source something the correct diameter.

-Kevin

PS Vikem rings are available on Amazon. Good prices.
Title: Re: My take on the BeePre
Post by: johnsonad on August 18, 2013, 05:37:27 AM
Yes PB, worse so with the EH's. The more microphonic the tube, the worse it is. Like Kevin stated, I need to raise my voice and the closer I'm to the preamp, the more it transmits it.

Kevin I like your train of thought. I would like to find something that would be excited first, minimizing the transmission to the tube.  What about a loosely formed cylinder of a thin metal?
Title: Re: My take on the BeePre
Post by: corndog71 on August 18, 2013, 08:28:32 AM
Acrylic tubes can be cut to size and may have better damping properties than a glass tube.
Title: Re: My take on the BeePre
Post by: Paul Joppa on August 18, 2013, 12:30:00 PM
Any air leak large enough for cooling will let most of the sound energy in, I suspect.

Until someone designs and conducts a suitable experiment, we don't know whether the tube or the chassis plate is responding, and hence whether or not a vibration-isolated socket will be of use.
Title: Re: My take on the BeePre
Post by: johnsonad on August 18, 2013, 12:37:24 PM
Thanks for the encouragement Paul  :P

Title: Re: My take on the BeePre
Post by: johnsonad on August 24, 2013, 07:15:10 AM
A short update.  I went ahead a swapped the 300 Ohm resistors for the 10H chokes that Xavier is using.  They have some break in (around 10 hours) and to be honest, I hear no change from the resistors.  I was lazy and haven't measured PS voltages after the change.  They get hot to the  touch after a few hours of use but so far so good. 
Title: Re: My take on the BeePre
Post by: xcortes on August 24, 2013, 07:17:23 AM
At least the chassis is heavier which should help with microphonics :)
Title: Re: My take on the BeePre
Post by: johnsonad on August 24, 2013, 07:25:00 AM
Good point my friend! 
Title: Re: My take on the BeePre
Post by: johnsonad on February 17, 2014, 06:38:46 AM
It's been a while since my last update but I'm continually impressed by this preamp! Today I decided to give the Dynamat Extreme a second chance as I'm running out of things to tweak and I had nothing better to do on a holiday morning. This time around I put at least two layers on as much surface area as I could to include the inside if the base. Well I'm happy to report that there is a small improvement to ring decay both in length and frequency.  The ring is shorter in duration and has less high frequencies to it.
Title: Re: My take on the BeePre
Post by: Deluk on February 27, 2014, 10:36:45 AM
This has been a very interesting read. The nearest valve connection for me is that I have been running a pair of Quad IIs for many years. They are currently having a rest, with a Luxman L30 doing duty at the moment. You say you're running out of things to tweak so I wonder if you would consider doing a complete volte face and see what seating your BeePre on a very lightweight stand, maybe just a slab of polystyrene, as a test. A light table is considered ideal for sprung turntables and might also present your tubes with a fundamentally different set of vibrations. Consider it a low cost experiment?
Title: Re: My take on the BeePre
Post by: johnsonad on February 27, 2014, 03:15:41 PM
I actually have it on the cement slab floor currently. All I can say is that it doesn't sound any worse. More to follow once I move the system around a little more.
Title: Re: My take on the BeePre
Post by: rockpassion on February 27, 2014, 05:14:56 PM
I have now had my BeePre for approximately 4 months.  It is slightly microphonic when I bump the stand or the case but otherwise I hear no negative feedback through the preamp and I have my speakers very close to the preamp.  Maybe I should get the silicone rings that Doc recommended and see if there is a change. 

Having said what I said, the musicality of this preamp is head-and-shoulders above my old FPII.  I have run it using a Curcio modified Dynaco MKIII and a Quicksilver Mono using EL34/KT77.  The Dynaco is very detailed with dynamic bass and pure highs, while the Quicksilver has some great mids and soundstaging.  But in both cases this preamp is stunningly musical. 

This preamp coupled with the Eros is a magical combination. 

Richard

Title: Re: My take on the BeePre
Post by: RPMac on March 02, 2014, 03:19:58 AM
Wait until you try it with a 6A3!!!
PJ out did himself with this amp!
Title: Re: My take on the BeePre
Post by: johnsonad on March 02, 2014, 05:11:57 AM
I did with the 8 pin equivalent, both the 6b4g and the Russian version. I really enjoyed the Russian tube and it's the only other pair I kept. For my system and listening pleasure the EML 300B sounds the best. It doesn't have the sparkle of some others but it has a midrange that comes to life somehow.
Title: Re: My take on the BeePre
Post by: RPMac on March 02, 2014, 07:31:26 AM
Aaron, I came real close to buying your EML's when you put them up for sale...I wish I had. EML's are definitely on my list to try. I wonder if the EML 20 is a possibility? It would add some gain that would help my system.
Title: Re: My take on the BeePre
Post by: johnsonad on March 02, 2014, 09:36:30 AM
Hi Robert.  I'll say that the EML's are not perfect by any means.  My buddies 6sn7 Akido preamp has better detail and highs but can't touch the intimacy of the EML's in the BeePre.  It's a compromise as is everything in audio.  300B's are always colored is some way.  I guess the trick is to find the right color for your system ;)

I know what you're saying with gain.  In my listening chair with the BeePre wide open I measure 95dB on sweeps.  Everything I've done to lower the gain though has resulted in increased fidelity.  I usually listen at around -6 to -18dB and have enough headroom even with a tape source for my listening levels.  I wouldn't go much lower in sensitivity with speakers than my current 95dB Altec's.  I miss the dynamics and punch of 100dB horns at times. 

One other reason to use them, they look great!
Title: Re: My take on the BeePre
Post by: johnsonad on March 15, 2014, 03:29:42 PM
A month out on the Dynamat mod and I'm happy with it.  The ring when adjusting volume or switching out source cables is noticeably shorter in duration and lower frequency.  It takes a little bit of work to get it cut and on the base plate but it made a difference in my system.

As far as placing the BeePre on the slab floor, this too seems to make some difference though subtle if any.  Best of all it's in my field of view while I listen :)  This also let to shorter cable lengths from pre to amp so I'm not sure the actual gain.

 
Title: Re: My take on the BeePre
Post by: johnsonad on May 09, 2014, 03:36:52 PM
A small update.  I put a plasma TV in the two channel system to kill two birds with one stone.  I found out the hard way that you can't have the BeePre too close to the plasma with out some interesting and annoying noise.  About three feet away and it is gone.  RFI is a PITA!

Title: Re: My take on the BeePre
Post by: johnsonad on May 26, 2014, 05:47:25 AM
I'm sitting here drinking my morning coffee and thinking about how content I am with my system. Yesterday I had an extended listening session that was very satisfying. It feels that I'm at a point were there is little left to fine tune.  In the last month I swapped the PF caps out in the amps for a positive gain. Thinking on the BeePre, the output caps are the only thing I would consider playing around with but prices for those big caps are prohibitive.  Many people here have enjoyed the ClarityCap MR.  I've had my eye on the Rike Audio oilers which have made a positive difference in two other builds.  Too bad dealers don't offer a demo on caps ;) Even a loan and swap program would be nice!

I really am happy with the sound but that doesn't mean I couldn't be happier with a few small changes. Someday, maybe, I'll have it just right to my ears and stop fooling around.  Until then I'll still have a smile on my face :)
Title: Re: My take on the BeePre
Post by: Paully on May 26, 2014, 07:13:41 AM
All right fine, you win.  I am ordering mine today.   :)
Title: Re: My take on the BeePre
Post by: johnsonad on May 26, 2014, 07:18:39 AM
About time! I thought you had given up on kit building ;)
Title: Re: My take on the BeePre
Post by: Paully on May 26, 2014, 07:27:48 AM
Ha! I am an addict, we swear we will never do it again and then...  Anyway, just put in my order!  Was going to talk it over with Grainger before I did but that guy is as addicted as I am.  I know what he is going to say.  Nothing like two junkies egging each other on.

As far as tubes go, I ordered my Bee Pre without tubes. I never liked EH.  I was very happy with Shuguang when my Paramounts were configured for 300B.  I am thinking I am just going to get a pair of those.
Title: Re: My take on the BeePre
Post by: Paul Birkeland on May 26, 2014, 07:50:04 AM
Thinking on the BeePre, the output caps are the only thing I would consider playing around with but prices for those big caps are prohibitive. 

No one is going to break down your door and chastise you if you use a cap smaller than 10uF on the BeePre.  We put the 10uF cap on there to be sure the frequency response characteristics when driving heavy loads would match the actual capabilities of the 300B.  If you're driving Paramounts, try a 1-3.3uF cap and call it good.

-PB
Title: Re: My take on the BeePre
Post by: Chris65 on May 26, 2014, 07:51:55 AM
I was very happy with Shuguang when my Paramounts were configured for 300B.  I am thinking I am just going to get a pair of those.

Which model were they Paully? 300B-98?
Just considering some back-ups/options.
Title: Re: My take on the BeePre
Post by: johnsonad on May 26, 2014, 07:54:15 AM
Microphonics are a huge issue in this preamp where as you wouldn't notice it as much in a power amp. The EH gold grids sounded surprisingly good in my BeePre but if you read back a few pages to my review of tubes, I ultimately settled on the EML solid plates.  Before you spend a big chunk of dough there are some cheaper tubes that sound very good in this preamp with low microphany.
Title: Re: My take on the BeePre
Post by: johnsonad on May 26, 2014, 07:57:48 AM
PB, I tried a 5uF cap at one point but it didn't have as much low end.  It's worth another try and I've got some random caps in that range to play with. Thanks!
Title: Re: My take on the BeePre
Post by: Paully on May 26, 2014, 07:59:45 AM
Been a while since I had them, but sure seems like they were the 300B-98.  Pretty darn sure.  And I did really like them.
Title: Re: My take on the BeePre
Post by: Paul Birkeland on May 26, 2014, 08:01:45 AM
Yeah, I would say buy a 10uF Solen, 4.7uF Solen, and 1uF Solen, then draw those kinds of conclusions. 

Into Paramounts, we are talking about -3dB points of 0.06Hz, 0.14Hz, and 0.64Hz.  This isn't to say that you won't hear a difference, but it's good to limit the variables as much as possible.
Title: Re: My take on the BeePre
Post by: johnsonad on May 26, 2014, 02:14:28 PM
Thank you PB, we had a fun afternoon of cap rolling.  I'm using 10uF KBG's in the BeePre now on extended leads.  I removed the caps and used alligator clip jumpers for the testing.   Today we did a little A/B/A/C/A/B with a 1.0uF Claritycap MR and a 1.5uF Rike Audio PIO using our usual test CD and some familiar recordings.  The MR was too polite and distant when compared to the other two.  Both of the PIO's were fuller.  The Rike started off good but after a few recordings we realized that it was much more rounded and made the system sound lower fidelity allowing us to listen to bad recordings for longer without pain but they didn't sound right at all.  The KBG's aren't perfect but in the current configuration they sounded the best of the three.  I'm using Rike's as PF caps in the Paramounts as they replaced KBG's.  This was an improvement but we may swap back to hear the difference after a month or so.  I've got some other caps in 1uF and above that we will try them in the BeePre sometime in the future.  I noticed no loss of bass with the 1.5uF caps and the 1uF caps sounded so far off that we didn't pay much attention to the low end.   
Title: Re: My take on the BeePre
Post by: Paully on May 26, 2014, 02:31:45 PM
How are you liking the KBGs as coupling caps?  I have some of those in the crossover for my Altecs.
Title: Re: My take on the BeePre
Post by: johnsonad on May 26, 2014, 03:09:58 PM
I'm using v-cap copper tefelons as couplers in the Paramounts. Overall I'm a big fan of KBG's and they are my go to cap until something works better.  Presently they are the output caps in the BeePre and the alternate PF cap in the Paramounts.
Title: Re: My take on the BeePre
Post by: Paully on May 26, 2014, 03:36:00 PM
What are the caps, all in all, that you changed out and what were the values?
Title: Re: My take on the BeePre
Post by: johnsonad on May 26, 2014, 03:57:39 PM
In the BeePre or Paramounts?
Title: Re: My take on the BeePre
Post by: Paully on May 26, 2014, 04:10:48 PM
Bee Pre, I am done tweaking my Paramounts!  I am rereading your post, I misunderstood it for some reason (I probably know, but wouldn't want to admit it).  I see you are just changed out the KBG's in the Bee Pre.  Got it, thanks.  I am going to collect all of the tweaks people are doing and ask some further questions in another post.

Anyway, I may do the KBG's or some Obligatto.  We'll see what I decide.  Thanks again.
Title: Re: My take on the BeePre
Post by: RPMac on May 27, 2014, 09:54:34 AM
After four months, my take on the BeePre is that it is excellent bone stock.
I don't seam to have a problem with microphonics.
The only thing I have changed is tubes...speaking of which, give the JJ 300b some thought. Also, the 6A3 is a drop-in replacement that I really like and NOS tubes are reasonable.

Title: Re: My take on the BeePre
Post by: Paully on May 27, 2014, 09:58:51 AM
I am looking at JJ right now.  I was a little concerned after all I read from Jim McShane on the quality of the JJ 8-pin tubes.  But if the 300B are still being built well, I am more than open to trying them.  Also, as the 6A3 is a drop-in replacement I will see about picking up a pair.  Thanks!
Title: Re: My take on the BeePre
Post by: Paully on May 30, 2014, 08:26:23 AM
I am thinking that I would rather have four inputs and I have no need of the balanced out.  So I thought i would just move the regular RCA out over to the balanced out spot and sub in some more RCA jacks to gain another input.  I have been searching and have come up with "Neutrik D Style" as stated on the product page.  So basically I need this, right?

http://www.mouser.com/ProductDetail/Neutrik/NF2D-B-2/?qs=sGAEpiMZZMvlX3nhDDO4AENKlXxvJs2PoyYpzPF8P7w%3d
Title: Re: My take on the BeePre
Post by: johnsonad on May 30, 2014, 08:53:26 AM
That's it. I had a couple sitting around from a previous project. I use that second set of outputs to drive a SEX amp for headphones. You could use it for subs too.
Title: Re: My take on the BeePre
Post by: Paully on May 30, 2014, 09:02:23 AM
Yea, I was thinking whether or not I really want to go to another input or keep it a second output.  But I have four inputs I want to use and don't use a sub or any other secondary out (and I don't plan on upgrading my Altecs anytime soon to anything that would require a sub).  So another input might be a lot more helpful.  Though I do think about building a headphone amplifier someday.  Hmmm, decisions...

Thanks!
Title: Re: My take on the BeePre
Post by: Paul Birkeland on May 30, 2014, 09:53:32 AM
You'll also need a different rotary switch: a 4P4T.  This is generally a 2 level rotary switch, which gets pricey. 

Title: Re: My take on the BeePre
Post by: Paully on May 30, 2014, 10:10:46 AM
Wow, you're right.  $100 and then you get started.  Thinking that a second RCA out is sounding better and better if not just wire it up as intended!  Thanks!
Title: Re: My take on the BeePre
Post by: johnsonad on May 30, 2014, 10:12:31 AM
I was thinking the same thing PB, that's a big ass switch.  Paully I rarely use a couple of sources and swap cables when needed.
Title: Re: My take on the BeePre
Post by: Paully on May 30, 2014, 10:16:09 AM
Just got off the phone with Grainger after talking though PB's post and that exact same thought occurred to me.  I use vinyl 99% of the time.  CD for most of the rest.  I do have a SACD player and an MP3 player.  Thinking if I need to switch between the two there is absolutely no way I use them enough to merit this sort of PIA and expense.  Think I will just swap them out manually when needed like you.  Its not that big of a deal.
Title: Re: My take on the BeePre
Post by: Paul Birkeland on May 30, 2014, 10:46:11 AM
You can also wire it completely stock and use a pair of these:
http://www.parts-express.com/xlr-female-to-rca-female-adapter--240-428 (http://www.parts-express.com/xlr-female-to-rca-female-adapter--240-428)
Title: Re: My take on the BeePre
Post by: Paully on May 30, 2014, 10:50:25 AM
That's cool, PB, even better idea then.  I am just going to wire the inputs and outputs stock.  Saves me some shipping and I get the adapters at Radio Shack or order them later.  Sweet!

Just out of curiosity, Johnsonad, what Elma selector switch did you use that still allowed the proper grounding scheme (if I understand the concept correctly)?
Title: Re: My take on the BeePre
Post by: johnsonad on May 30, 2014, 02:29:23 PM
I'll PM you this weekend Paully.  I suck at switches and the BH team would be able to tell you off the top of their collective heads.  I'm into a bottle of wine at the moment and don't want to risk flipping the BeePre until morning :)
Title: Re: My take on the BeePre
Post by: Paully on May 30, 2014, 02:34:46 PM
Enjoy the wine!  I have some seriously special beer upstairs, think I will go get some.  And I think we have a couple of weeks before I would need to know anything!

Edit: beer brewed by Trappist monks, and a Bottlehead Eros, Foreplay, and Paramounts feeding some Altec Model 19s.  Must be Friday night!  Too much fun!
Title: Re: My take on the BeePre
Post by: Skip Pack on May 31, 2014, 09:29:29 AM
A good alternative to a complex rotary switch is two 4pdt microswitches. Each of four (or three) inputs can be wired to the output bank of eyelets and the center eylets can be wired in parallel to the preamp circuit input. This switches four stereo inputs and grounds into the preamp. Michel Percy sells these for about $11 each, and they are quality switches (and very small). I've done these many times and it works very well.

Skip
Title: Re: My take on the BeePre
Post by: johnsonad on June 06, 2014, 12:24:43 PM
Thanks Skip, I'm going to give it a try on my next preamp build.
Title: Re: My take on the BeePre
Post by: Paully on June 27, 2014, 05:48:05 PM
Got it done, will post a picture with the big chokes on the chassis.  Sound was stunning.  Once again I was shocked by how much better something can make my system sound.  I didn't realize there was this much improvement left to be had.  The Bee Pre is magnificent.
Title: Re: My take on the BeePre
Post by: johnsonad on June 27, 2014, 08:16:49 PM
Well said! BH really got it right with that preamp
Title: Re: My take on the BeePre
Post by: johnsonad on November 29, 2014, 05:51:26 AM
Last week we demo'd a First Watt M2 in the system that unfortunately didn't make the cut.  It did though shake up the system some and the end result is fantastic.  Change can be a good thing and my system needed it.

The BeePre hadn't been updated since we switched from the 19's to the Altec 755A's with Rythmik subs.  These little drivers are like microscopes back into your system and until last night, we didn't feel like they were right.  First, attached are a couple of photos of the Dynamat Extreme applied to the base and the bottom of the chassis plate.  It makes a difference but takes a lot of work to get it on there. 

A wondering trip to get to the end.... Tubes.... We had been using the EML solid plates.  If you have read through this thread, it took a bit of work to get them to work right but they have a special sound to them.  For fun, we took the EML mesh plates and plugged them in and they sounded better, more correct.  We were both impressed but they will not work in the BeePre and they felt distant, like listening through something.  One last attempt at tubes ended up with the Russian 6C4C's back in and they sounded nice and as I've said before, are the least microphonic of any tube I've tested.  Not perfect but better than the EML's.  To fill the void of the M2, I dug out the old rebuilt Quad 303 so I could revisit the Paramount-ish amps.  The Quad bested the M2 (and my Paramount-ish amps) in every way and really took control of the speakers with a beautiful sound.  I guess having been designed to drive 57's, it can drive and damp about anything, including the 755A's in WE boxes. 

The EML's draw more current than the original WE tube and I had to mod the BeePre to accommodate them.  For the life of me I couldn't find the 8 Ohm resistors and in the spirit of trying something new, I ordered some Caddock thick film resistors (4 Ohms) to fill the void of the paralleled 8 Ohm resistors.  Attached is a bad photo of their installation which went well.  The Caddocks are 30 watt rated but need a heat sink.  I drilled a couple of holes in the plate and super glued them in.  They put off some heat but I can still hold my fingers at the top of the heat sink for 2 seconds.  I need to borrow my buddies heat gun again to get some real numbers off of the fins, but they are well within the temp specs and the chassis plate is much, much cooler now.  I didn't hear an immediate difference in sound and didn't expect to.  This was more to see if it would work.

Now updated, the system was sounding better but still a little off and painful for long sessions.  Last night I pulled a Grainger and starting testing output caps on test leads.  I had been using KBG 10uF's and first up tried the Rike Audio PIO's.  This actually wasn't an improvement but did change the sound.  Next up, a pair of Panasonic 10uF that had been in a different build.  They sounded better than the Rike's but nothing to write home about.  Last up was a pair of Auricap 5uF's.  These sounded great!  A remarkable improvement over all of the others tested.  I got my wife to actually sit down and listen to them and even she agreed it was better but to me they still were not quite there.  So again following Grainger's lead, I bypassed them with a pair of V-Cap Teflons 0.047uF that were sitting around and that really took it to the next level.  That little bypass cap added considerable depth and clarity to the sound.  We listened for a couple of hours after that and this is the best those little 755's have sounded to date!

Change is good and it's nice to have a stash of random caps to try.  I can only imagine what's it like for guys and gals who can't make mods to their own gear.....

Title: Re: My take on the BeePre
Post by: Grainger49 on November 29, 2014, 06:12:23 AM
It is a sickness but it keeps us safe and off the streets.

Glad to be of help/inspiration.


(http://i244.photobucket.com/albums/gg7/Grainger49/Smiles/TipHat.gif)
Title: Re: My take on the BeePre
Post by: Hank Murrow on November 29, 2014, 07:26:02 AM
Seconded, Aaron;

All my Custom BH pieces have been outfitted with V-caps(Cu & Sn) and I love them. Got to qualify this by saying that they were built by Paul Birkeland from the start with them, so I have not heard anything else in my system, though we did a favorable comparison in the BH big system in Poulsbo. I am eager to hear the BH DAC with my Oppo DVP95 when the DAC arrives in February.

Cheers, Hank in Eugene
Title: Re: My take on the BeePre
Post by: johnsonad on December 20, 2014, 01:15:39 PM
I've been enjoying the BeePre and the system more than ever with this tube and cap combo.  To get it right I ordered a pair of 200v 10uF Auricap XO's and a pair of 0.1uF V-Cap Teflons to replace the 0.047uF V-Caps and 5uF Auricaps (600v) that are in there currently.  My break in rig started acting up and I'm surprised it didn't cause a fire.  I put the new caps into the BeePre today and started the burn in process over again using a wave file through the Oppo to the BeePre on repeat.  It's going to take a while but these new caps fit a lot better then the 600v version.

I also picked up a pair of 40's Ken Rad double flat plate 6B4G's to compare against the Russian tubes.  They are significantly more microphonic.  Tapping on the BeePre base causes a boom through one channel of the speaker.  Thankfully as long as I'm not thumping on the preamp they sound good but not any better than the Russian tubes rather, quite the same.  For the money, those Russian tubes are hard to beat!

More to follow as they break in.  Thankfully those V-Cap leads are so stiff that I zip tied the Auricaps to them and the stand off quite nicely.
Title: Re: My take on the BeePre
Post by: HF9 on December 20, 2014, 04:56:25 PM
Neat idea using the Dynamat Xtreme to dampen the wood frame. I always keep plenty of the stuff in my workroom, usually for headphones and speakers, however I never thought of this type of application. Do you think it made any difference? 
Title: Re: My take on the BeePre
Post by: johnsonad on December 20, 2014, 05:51:25 PM
I do feel it made a difference as did the tall Herbies Tender Feet and placing the BeePre on the slab floor. Every little bit helps!
Title: Re: My take on the BeePre
Post by: Paully on December 21, 2014, 03:33:53 AM
Interesting.  I have noticed absolutely no microphonics in my Bee spree using JJ 300B and from posts it seems the tubes chosen seem to make a big difference.  It's not like a circuit can be microohonic, right?  So it has to be the tubes?  Are 300B more prone to microphonics?  I noticed some 7N7 in my old FPIII were much more prone to it.
Title: Re: My take on the BeePre
Post by: johnsonad on December 21, 2014, 04:32:01 AM
It's the tubes.  Some are more prone than others. 
Title: Re: My take on the BeePre
Post by: badman on December 22, 2014, 07:57:07 PM
It might be buried in the thread somewhere- where did you source those knobs?  They're mega-cool!
Title: Re: My take on the BeePre
Post by: johnsonad on December 23, 2014, 03:30:26 AM
They are from a 1920's RCA HAM radio. You can get reproductions on EPay or the Audioasylum Trader.
Title: Re: My take on the BeePre
Post by: aragorn723 on December 23, 2014, 01:09:31 PM
Hi Aaron,

How did you mount the caps?  Looks like a standoff with one of those zip ties that has a loop you can screw into?

Thanks

Dave
Title: Re: My take on the BeePre
Post by: johnsonad on December 23, 2014, 02:50:56 PM
No mounting. The leads on the V-caps are stuff solid core. I zip tied the Auricaps to the V-Caps. Nothing else needed.

So far so bad on break in. I'm listening to them everyday and they are slowly improving. It could be the value changes but I wonder if the new XO Auricaps sound different from the old style.
Title: Re: My take on the BeePre
Post by: aragorn723 on December 23, 2014, 03:52:06 PM
Hmm so i'm guessing they aren't very heavy?  I hear the teflons take a long time to burn-in (200+ hours) so hang in there.  They will pay off in the end!

Dave
Title: Re: My take on the BeePre
Post by: johnsonad on December 23, 2014, 04:21:11 PM
No, the XO's are very light.  I've been using V-Caps in other builds for a while now.  It's long process but usually worth it. 
Title: Re: My take on the BeePre
Post by: johnsonad on December 28, 2014, 09:36:10 AM
The Auricap XO's and V-Caps were removed and replaced by the older style Auricap (5uF 600v) and 0.047uF V-Cap bypass that originally sounded good.  The XO's don't sound as good to my ears in this system as the older caps do.  The downfall was securing them as these 600v caps are huge!  Mine are strapped down with good ole dental floss to whatever I could secure them to and keep them from leaning against the heat sinks.  It's not pretty but it works :)

I measured the voltages of the 6B4's that are in there with the 4 Ohm resistors.  Like Xavier experienced, both pairs of tubes are current hungry.  The Kenrads are 6% off at 5.93v/5.87v and the 6C4C's are 8% off at 5.76v/5.79v.  I've got a lower valued resistor on order and will report back the findings once they have been retested. 
Title: Re: My take on the BeePre
Post by: HF9 on December 28, 2014, 06:47:36 PM
Well you've got me drinking the Kool-aid Aaron ;) I just ordered some 50mil Butyl sound damping sheets for my BeePre base I'm assembling now.
Title: Re: My take on the BeePre
Post by: johnsonad on January 01, 2015, 09:30:22 AM
This morning I replaced the 4 Ohm resistors with 3.3 Ohm.  It was the only other value available from Mouser in this type of resistor and I got lucky.  Here are the before and after measurements with the Russian 6C4C tube.

Before (4 Ohm):
5.76v/5.79v (8%)

After (3.3 Ohm):
6.27v/6.22v (1%)

Can't ask for better than that!  As long as I stick with this tube, I should be golden.  I'm done with BeePre updates for the foreseeable future.  Now to get my Paramount-ish amps up to speed.   
Title: Re: My take on the BeePre
Post by: johnsonad on January 02, 2015, 12:42:54 PM
Well you've got me drinking the Kool-aid Aaron ;) I just ordered some 50mil Butyl sound damping sheets for my BeePre base I'm assembling now.

Report back on this when finished.  I would like to see how it looks when you consider this from the beginning and not an after thought as was my case. 
Title: Re: My take on the BeePre
Post by: johnsonad on January 02, 2015, 12:59:41 PM
A pic of the new cap installation.
Title: Re: My take on the BeePre
Post by: wullymc on January 04, 2015, 05:59:31 AM
Hey Aaron,

Very nice thread about your build.   I have noticed that the last two images with the V-Caps you have installed them 2 different ways (looking at the left side).  Eg. the green wire to the right, then the green wire to the left.

I have read them following installation instructions but don't know if you have taken this into consideration:

http://www.v-cap.com/installation-notes.php

You know better than me though!  I will be eventually using V-Caps but don't know how to determine which soldering location would be the lowest impedance path to ground.

Take care...Dave
Title: Re: My take on the BeePre
Post by: johnsonad on January 04, 2015, 06:10:58 AM
Dave,

They are installed correctly in the second photo (with larger caps) though it looks odd. The BeePre's outputs run down the center of the chassis this why you see both reds in the center and the green/black ends on the outsides of the chassis.

I had to look it up myself and had them installed backward the first time around. I'm not sure it makes much of a difference having not compared them wired both ways but I'm happy with it wired this way.
Title: Re: My take on the BeePre
Post by: johnsonad on February 22, 2015, 06:45:10 AM
A little update.  I purchased a pair of Elrog 300B's and I briefly put them into the BeePre today.  With very little listening time I was impressed by the sound, so much so that if I can sell off some extra gear, I may consider buying a second pair for the BeePre (this pair is for the Paramounts). 

Compared to the Russian tubes in their now, the Elrog's are significantly more microphonic.  The Russians I can beat on the top plate and have very little ring.  The Elrog's on the other hand ring like a bell.  I might add, it's a beautiful sounding bell but they ring none the less.  I find they are a little noisy too in the Paramount but I couldn't get a feel for the amount of noise increase their would be with them in BeePre and the EML's in the Paramounts.  It's a very small increase but an increase none the less. 

BTW, the red rings sit on the tubes just fine for about 2 seconds.  Once they heat up a little they become slick and they slide off the side of the tubes. 
Title: Re: My take on the BeePre
Post by: KevO on March 01, 2015, 11:28:12 AM
Congratulations on getting Elrog 300b's. I am glad you are enjoying them.

Thanks for the feedback on their microphony too. Nothing is perfect unfortunately.

I was just changing music and sneezed toward the BeePre. An amplified sneeze is scary sounding. The EH's are like microphones. Time for more damping.

Kevin
Title: Re: My take on the BeePre
Post by: johnsonad on March 01, 2015, 11:47:33 AM
Every little bit helps Kevin. The efforts are worth it though!